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I was working on a program in Eclipse. I went to run it, and ran into some 'unknown source' errors, so I tried to reinstall my java and ran into some annoying errors. First thing I ran into was an error saying that Z: is an invalid drive during the uninstall of the JRE.

I used to have a Z partition on my drive with some stuff installed to it, but that has since been changed. I tried again, and ran into a 1723 error, which from what I've found is a problem with the Windows Installer. I'm running Windows 7 and haven't found anything so I can reinstall it. I ran into the same 1723 error when trying to install java over top of the failed uninstall. Any ideas?

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I had a similar problem on my Windows 7 box where I was trying to uninstall Java and do a clean install of a newer version. Something got messed up and I would get the 1723 error message during the uninstall and attempted reinstall. Here's information about how I was able to fix the problem, and maybe this will help you:

Look at the log files for the uninstall/reinstall. On Windows 7 they can be found at c:\users\username\AppData\Local\Temp\

The java_install.logdidn't show any extra information, but I had several MSI##### log files that contained error messages about the failed uninstall. The message was: Error 1723.There is a problem with this Windows Installer package. A DLL required for this install to complete could not be run. Contact your support personnel or package vendor. Action UninstallJRE, entry: MSIUninstallJRE, library: C:\Program Files\Java\jre6\bin\regutils.dll

There was indeed no regutils.dll file, and not even the bindirectory was there. So I copied over a regutils.dll file from another computer, ran the uninstaller, and it worked. Then the new clean install of Java also worked.

So take a look at your logfiles and hopefully that will give you more detailed information about the 1723 error.

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Thanks this has been driving me nuts for months! – slm Jan 31 '12 at 16:22
To complete this answer: These logfiles will be written into the path %USERS%\AppData\Local\Temp – reporter Apr 17 '13 at 11:19

I ran into the same situation and I could find another way to solve this issue.

I downloaded the offline version from JRE6 and did install this - with default preferences- first. After that I installed the offline JDK version, also with default preferences. When I got the a positiv feedback from installer, I deinstalled both versions and installed the pure JDK in a folder of my choice.

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